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Y Imai

Publications and source records attributed to Y Imai.

At least 1,045 records · Page 58Linked to original sources
PubMed1988

Ultrasonic evaluation of cervical metastatic lymphadenopathy.

We investigated the location, size, and shape of cervical lymph nodes in head and neck cancer, using a 7.5-MHz ultrasound scanner. First, the different criteria for normal size were obtained for cervical lymph nodes in each region; lymph nodes greater than 9 mm in thickness in the internal jugular chain or greater than 7 mm in thickness in the submandibular and submental chains should be suspected of harboring metastatic foci. Second, metastatic nodes showed a more rounded configuration than nonmetastatic ones. Third, a comparative study of metastatic lymph nodes between the in vivo and in vitro ultrasonograms and the corresponding histopathological findings disclosed that an echogenic region in an ultrasonogram of a metastatic node was caused by coagulation necrosis, and a cystic area of liquefaction necrosis.

Carcinoma, Squamous Cell↗
PubMed1988

Clinical application of a new vital staining method for the conduction system during heart operations.

A new method for vital staining of the conduction system during heart operations, the iodine gas method, was used in 12 patients. The right bundle branch stained well in all cases, and could be confirmed by the naked eye. The conduction system was not damaged by the staining procedure. The iodine gas used in this method had no adverse effects on thyroid function (thyroxine, triiodothyronine, thyroxine binding globulin, protein bound iodine) or liver function (serum glutamate oxaloacetate transaminase, serum glutamate pyruvate transaminase, lactic dehydrogenase). This method, therefore, was found to be valuable and without complication for preventing conduction disturbances during cardiac operations.

Cardiac Surgical Procedures↗
PubMed1988

Long-term results of the clinical use of an expanded polytetrafluoroethylene surgical membrane as a pericardial substitute.

We report our long-term experience with the clinical use of an expanded polytetrafluoroethylene surgical membrane as a pericardial substitute in 61 children with congenital heart disease. Twenty-three of these children underwent reoperation successfully, and advantages of the membrane in resternotomy and dissection of the pericardial space were recognized. We have so far experienced no major complications from the use of an expanded polytetrafluoroethylene surgical membrane. We conclude that the clinical use of an expanded polytetrafluoroethylene surgical membrane as a pericardial substitute is valuable in children with congenital heart disease who are expected to undergo reoperation in the near future.

Child↗
PubMed1988

[A valved conduit replacement for a calcified homograft 12 years following a Rastelli operation: a case report].

A 25 year-old male with transposition of great arteries, ventricular septal defect and pulmonary stenosis successfully underwent Rastelli procedure with aortic homograft in 1969. After the procedure he grew up and became an engineer without any complaints. However, gradually his homograft degenerated with calcification and the pressure gradient between pulmonary artery and right ventricle increased to 77 mmHg in systolic phase. Twelve years after the conduit repair, we operated upon and enlarged the ventricular septal defect, repaired the residual interventricular shunt, removed his homograft and, replaced it with the Hancock valved conduit from the right ventricular outflow tract through cardiopulmonary bypass. On postoperative cardiac catheterization, the pressure gradient decreased, and the patient returned to his work.

Adult↗
PubMed1988

Interviral homologies of the 30K proteins of tobamoviruses.

The 30K protein of tobacco mosaic virus was recently confirmed to be involved in cell-to-cell movement of the virus. To characterize common structural features of the 30K protein, the nucleotide sequence of the 30K protein gene of cucumber green mottle mosaic virus (CGMMV, a member of the tobamoviruses) RNA has been determined. The CGMMV 30K protein is composed of 264 amino acids with a calculated molecular weight of 28,800. Comparisons among the 30K proteins of tobamoviruses show that the 30K proteins are composed of a rather conserved N-terminal two-thirds and a less-conserved C-terminal one-third. The N-terminal two-thirds contain two particularly well-conserved sequences, one of which contains amino acid substitutions that result in temperature-sensitive cell-to-cell movement. The C-terminal region is further divided into three subregions by distribution of charged amino acid residues.

Amino Acid Sequence↗
PubMed1988

[Aortic valve replacement in children associated with enlargement of aortic annulus].

Between February, 1983 and August, 1987, twelve children, aged from 2 years to 16 years, underwent aortic valve replacement associated with enlargement of aortic annulus successfully. According to the form of the left ventricular outflow tract obstruction, enlargement of aortic annulus was performed by Konno procedure in eight cases, by Nicks procedure in three cases and by Manouguian procedure in one case. In Manouguian procedure, mitral valve replacement associated with enlargement of mitral annulus was carried out simultaneously. In Konno and Manouguian procedures, the diameter of aortic annulus was enlarged from 180% to 200% compared with the original annular size, whereas in Nicks procedure, the diameter was enlarged around up to 110%. St. Jude Medical valve, of which size ranged from 21mm to 25mm, was employed in these procedures. All these children survived operation, and the post-operative follow up period ranged from 1 month to 55 months. There was one late death eleven months after Konno procedure because of respiratory failure resulting from pulmonary hypertension which persisted postoperatively. The remaining eleven children are surviving well after procedure. These results suggest that aortic valve replacement associated with enlargement of aortic annulus is an acceptable procedure in children with small aortic annulus or sub-aortic stenosis.

Adolescent↗
PubMed1988

Involvement of the hypothalamo-pituitary-adrenal axis in the control of circadian blood pressure rhythm.

The circadian blood pressure rhythm was compared between patients with Cushing's syndrome and those with essential hypertension or primary aldosteronism. In patients with essential hypertension or primary aldosteronism, clear nocturnal falls in systolic and diastolic blood pressure and the heart rate were observed. In contrast, in patients with Cushing's syndrome there was no nocturnal fall in blood pressure, and even a rise in some cases. In all cases with Cushing's syndrome, there was a nocturnal fall in the heart rate. Exogenous glucocorticoid abolished a nocturnal fall of blood pressure in patients with chronic glomerulonephritis or systemic lupus erythematosus, but did not affect nocturnal falls in the heart rate. These results indicate that the normal circadian rhythm of blood pressure may be regulated, at least in part, by the hypothalamopituitary-adrenal system.

Blood Pressure↗
PubMed1988

Surgical anatomy of the atrioventricular conduction bundle in tetralogy of Fallot. New findings relevant to the position of the sutures.

To avoid three of the causes of right ventricular end-diastolic pressure elevation, complete heart block, residual leakage, and fixing of tricuspid septal leaflet, we studied detailed anatomy of the posteroinferior corner of the ventricular septal defect of tetralogy of Fallot in 81 specimens. A new stitching method was applied in 79 patients with tetralogy of Fallot. Sixty-eight specimens (84%) had perimembranous outlet ventricular septal defect with a membranous flap 4.5 +/- 2.6 mm long. Thirteen (16%) had a muscle bar separating the defect from the central fibrous body area. The width was 5.8 +/- 1.7 mm. Microscopic study revealed that the membranous flap is a safe structure for suturing because of the thick posterior extension of the trabecular septomarginalis. In the clinical application of a new stitching method that uses the membranous flap, all patients showed sinus rhythm and no patient had complete heart block. We conclude that a membranous flap can be used safely as a suture line to avoid conduction tissue damage without using the tricuspid septal leaflet.

Atrioventricular Node↗
PubMed1988

[Platinum concentrations in human tissue after administration of cisplatin].

Using flameless atomic absorption spectrophotometry, platinum concentrations in tissue samples were determined to clarify the distribution and accumulation of platinum in the human tissue after administration of cisplatin. Tissue samples were obtained at the time of autopsies or operation from 14 patients who were given cisplatin 0.7-20.1 mg/kg. Platinum concentrations were highest in the liver and testicle, high in the kidney, lung, heart and spleen, and lowest in the brain. In most organs except the brain, the tissue platinum concentrations increased exponentially according to the total dose of cisplatin. Platinum concentrations in metastatic tumors were generally somewhat lower than those in the normal parts of the organs, with the exception of cerebral metastasis. However, some of the metastatic tumors in the lung and brain showed higher concentrations than those in normal parts of the lung and brain, respectively.

Adolescent↗
PubMed1988

Simultaneous determination of catecholamines and serotonin by liquid chromatography, after treatment with boric acid gel.

We describe a liquid-chromatographic method for simultaneously determining norepinephrine, epinephrine, dopamine, and serotonin in 0.5 mL of human plasma. These analytes are purified on boric acid gel from Aldrich, separated on a reversed-phase C18 column, and detected electrochemically at +600 mV. Absolute recoveries of internal standards were 84% for 3,4-dihydroxybenzylamine and 57% for N-methylserotonin. Reproducibility was good to excellent, depending on the concentration of the analytes. A chromatographic run is complete in 40 min, but this can be shortened by about half when the determination of only serotonin is required, by increasing the column temperature from 40 degrees C to 60 degrees C.

Adult↗